Corporation Tax Penalties Are Changing in 2026 — What You Need to Know
New Corporation Tax Penalty Regime
HMRC has been gradually introducing a new points-based penalty system. Here's what limited company directors need to know.
Current CT600 Penalties
| How Late | Penalty |
|---|---|
| 1 day late | £100 |
| 3 months late | Another £100 |
| 6 months late | 10% of unpaid tax (HMRC estimate) |
| 12 months late | Another 10% of unpaid tax |
Corporation Tax Payment Deadlines
Your corporation tax payment is due 9 months and 1 day after the end of your accounting period. This is separate from the CT600 filing deadline (12 months after period end).
Example: If your accounting period ends 31 March 2026:
- Payment due: 1 January 2027
- CT600 filing due: 31 March 2027
Interest on Late Payment
HMRC charges interest on late corporation tax payments from the day after the due date. The current rate is 7.25% (as of 2026).
Large Companies: Quarterly Instalments
Companies with profits over £1.5 million must pay corporation tax in quarterly instalments, starting in the 7th month of the accounting period.
How to Avoid Penalties
- Know your deadlines — use FileMinder to track them automatically
- File and pay early — don't wait until the due date
- Set up Direct Debit with HMRC for automatic payment
- Keep your accounting records up to date throughout the year
Never miss a filing deadline
FileMinder automatically tracks every UK company compliance deadline for you.
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